L5811 — Addition, endoskeletal knee-shin system, single axis, manual lock, ultra-light material
L5811 is a HCPCS Level II code for addition, endoskeletal knee-shin system, single axis, manual lock, ultra-light material. It belongs to the Orthotic and Prosthetic Procedures and Devices section. Whether Medicare pays it depends on the coverage rule below.
Medicare coverage: Carrier judgment
Coverage is decided by your Medicare contractor, not by national policy. Whether this is paid depends on the LCD for your jurisdiction and on what the documentation supports.
From the coverage field of the CMS Alpha-Numeric HCPCS File, release 2026Q3-Jul. This states Medicare’s position on the code, not on your particular claim.
Medically Unlikely Edits — units per day
The most units of L5811 Medicare will pay on one date of service. Bill more on a single line and it is denied. The limit is not the same in every setting, so the row that matters is the one matching the claim you are building.
- practitioner
- 0 — never payable MAI 3 — Date of Service Edit: Clinical · CMS Policy
- outpatient
- 2 units MAI 2 — Date of Service Edit: Policy · Anatomic Consideration
- DME supplier
- 2 units MAI 2 — Date of Service Edit: Policy · Anatomic Consideration
The adjudication indicator decides whether exceeding the limit is worth appealing at all: MAI 1 is a line edit you can support with documentation, MAI 3 is a date-of-service edit that is also appealable, and MAI 2 is absolute — no documentation overrides it. CMS MUE 2026Q3.
The CMS record for L5811
- Long descriptor
- Addition, endoskeletal knee-shin system, single axis, manual lock, ultra-light material
- Short descriptor
- Endo knee-shin mnl lck ultra
- Added
- January 1, 1988
- BETOS
- D1F
- Pricing indicator
- 38 — DMEPOS
The official wording. This is what the code means.
CMS's 28-character form, which is what shows up on a remittance advice.
When CMS introduced the code.
Berenson-Eggers Type of Service — CMS's own analytic grouping.
Orthotics, prosthetics, prosthetic devices and vision services. Price subject to floors and ceilings.
Codes adjacent to L5811
HCPCS has no hierarchy — related items simply sit next to each other in the numbering. If L5811 is not quite right, the correct code is very often within a few positions of it.
- L5780Addition, exoskeletal knee-shin system, single axis, pneumatic/hydra pneumatic swing phase control
- L5781Addition to lower limb prosthesis, vacuum pump, residual limb volume management and moisture evacuation system
- L5782Addition to lower limb prosthesis, vacuum pump, residual limb volume management and moisture evacuation system, heavy duty
- L5783Addition to lower extremity, user adjustable, mechanical, residual limb volume management system (with or without lamination kit)
- L5785Addition, exoskeletal system, below knee, ultra-light material (titanium, carbon fiber or equal)
- L5790Addition, exoskeletal system, above knee, ultra-light material (titanium, carbon fiber or equal)
- L5795Addition, exoskeletal system, hip disarticulation, ultra-light material (titanium, carbon fiber or equal)
- L5810Addition, endoskeletal knee-shin system, single axis, manual lock
- L5812Addition, endoskeletal knee-shin system, single axis, friction swing and stance phase control (safety knee)
- L5814Addition, endoskeletal knee-shin system, polycentric, hydraulic swing phase control, mechanical stance phase lock
- L5816Addition, endoskeletal knee-shin system, polycentric, mechanical stance phase lock
- L5818Addition, endoskeletal knee-shin system, polycentric, friction swing, and stance phase control
- L5822Addition, endoskeletal knee-shin system, single axis, pneumatic swing, friction stance phase control
- L5824Addition, endoskeletal knee-shin system, single axis, fluid swing phase control
- L5826Addition, endoskeletal knee-shin system, single axis, hydraulic swing phase control, with miniature high activity frame
- L5827Endoskeletal knee-shin system, single axis, electromechanical swing and stance phase control, with or without shock absorption and stance extension damping
Questions about L5811
What is HCPCS code L5811?
L5811 is a HCPCS Level II code for addition, endoskeletal knee-shin system, single axis, manual lock, ultra-light material. It sits in the Orthotic and Prosthetic Procedures and Devices section.
Does Medicare cover L5811?
The CMS HCPCS file marks L5811 as "Carrier judgment". Coverage is decided by your Medicare contractor, not by national policy. Whether this is paid depends on the LCD for your jurisdiction and on what the documentation supports.